ΔE 17.0, loose: different enough that you should pick on purpose. Charred Brown is noticeably lighter, more muted than Redwood Brown.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 17). Charred Brown is noticeably lighter, more muted than Redwood Brown.
The same difference applies the other way round: Redwood Brown is noticeably darker, more saturated.
ΔE is the colour difference between our two swatch estimates: under about 6 is close, over about 15 is loose. Real paints also differ in finish, coverage and how they thin, so test before you commit.
See Redwood Brown on the colour wheel See Charred Brown on the colour wheel
All matches: Redwood Brown equivalents · Charred Brown equivalents